Valve mechanism



Aug. 13, 1940. 2.21 1,013

H. L. HOSTERMAN VALVE MECHANISM Filed 001;. 4, 1938 2 Sheets-Sheet l 6'INVENTOR.

v lfi y ATTORNEY.

Aug. 13,1940- H. L. HOSTERMAN 221L013 VALVE MECHANISM Filed Oct. 4, 19382 Sheets-Sheet 2 INVENTOR. flak/y 1., floxfe/vzra/z ATTORNEYJ;

Patented Aug. 13, 1940 PATENT. OFFICE VALVE MEGHANISIVI Harry L.Hosterrnan, Akron, Ohio, assignor of one-fourth toGeorge W. Perks andone-fourth to Donald Glottwald, Akron, Ohio Application October 4,

I j '7 C laims.

This invention relates to valve mechanism for use in internal combustionengines and is more particularly directed to mechanism of the type.

employing a' single valve through which the intake gas is passed to thecylinder and the exhaust gas removed therefrom.

Mechanisms of this general type are very old and it has frequentlybeen'proposed to provide a single poppet valve providing access to thecylinder for both the exhaust and intake gases and combined with asecondvalve to alternately: effect a fuel intake or fuel discharge asdesired. These prior mechanisms have been subjectedto the disadvantagethat both the intake and exe' haust lines were open at-the same time foran appreciable and uncontrolled period during operation- This timeperiod was sufiicient to blow exhaust gas back into the intake line andnullify the otherwise efficient characteristics of the design. In somecases the hot exhaust gas would ignite the intake gas and pre-explodethe fuel before it had passed beyond the second valve. With mechanismsof this type, it has heretofore not been possible to control the degreeof overlap between the period the exhaust valve is open and the periodthe intake valve is open. Expressed in another way,'the inertia andspeed limitations in valve mechanisms, from a practical standpoint,prevent the instantaneous opening of a valve. Therefore the valve mustopen as a result of appreciable movement.

I have found that if I provide a sleeve valve which may simultaneouslycommence to move to seal one port and at the same time continue to aseal the other port until such time as the operating characteristics ofthe engine demand that the latter port be opened I caneffectuallyemploya single poppet valve to function as both" intake and exhaust to thecylinder. In certain cases it is desirable to maintain one port entirelyclosed during the period the other port isopen and in other engines.with other operating characteristics, what I term a controlled degree ofoverlap of valve opening should be employed to allow both ports to beopen during a short period of the engine cycle. This period. should notexceed 60 degrees of crankshaft rotation or 30 degrees of camshaftrotation, the latter shaft rotating at one-half thecrankshaft speed.

-The cardinal object ofthis invention has been to provide a valvemechanism for internal vcombusticn engines which will permit of a largearea of cylinder valve with respect to a given cylinder 55 diameter thanhas heretofore been possible ,and

1. 38, Serial or 233,323

(01, 123.79) I a .thus to improve the volumetric efficiency of the enine."

An additional object of my invention has been to overcome the operatingdisadvantages with former related constructions by providing a valve 1mechanism with a controlled degree of overlap ,for the most efficientoperation of the engine by which there isno possibility of both theintake and exhaust lines being open to the cylinder bey;ond a desiredtime; As a related object of my invention I amgenabled by the valvemechanism itself to time the intervening period between closing theexhaust line and opening the intake line. 3

To the accomplishment of the foregoing and related ends, said invention;then, consists of the means hereinafter fully described and particularlypointed out in the claims; the annexed drawings and the followingdescription setting forth in detail certain structure embodying theinvengo tion, such disclosed means constituting, however, but oneofvarious mechanical means inwhich the principle of the invention may beused.

In said annexed drawings:

Figs; 1, 2, 3-and 4 are similar sections through my improved valvemechanism showing respectively the position of the parts during thepower, exhaust, intake and compression strokes; and V Fig. 5 is asection through Fig. 2, as indicated by the lines 5-5 thereon. g

' Referring now to the drawings; I provide a cylinder block I0 in whichis formed one or more cylinders H, accommodating a-piston 12, to which 7is connected the usual connecting rod M for engagement with thecrankshaft. .A head I5 is i-35 bolted to the block-I0 and supports thevalve mechanism hereafter described. 7

The head it is formed with an intake conduit H and an exhaust conduit l8opening into a valve casing 28, which communicates with an 4oexplosion-chamber 22 in communication with the .main cylinder H.

A poppet valve 25 seats against the .cylinder head at .26 and isprovided with a stem 23slidably receivedin a core 38. as-a valve stemguide, includes a head portion ti-by which the same is secured to-thehead withinthe'valve casing 20 and in position to effective-j lyseal thesame at its ,upper end. An annular boss 33, formed as indicated in thedrawings, on 50 the lower portion of thecore coacts with the valvecasing wall to form a sliding valve seat as hereaftendescribed. x

To seal the intake conduitl'l from the exhaust conduit I8, a sleevevalve is provided recip- .55

The core which functions rocable between the boss 33 and the adjacentcasing side wall. As best shown in Figs. 2 and 3, the sleevecross-section is of such length and configuration that during itsdownward movement to seal the exhaust conduit it will maintain thepassage from the intake conduit closed for the desired period of time.sleeve by which this is accomplished .may be varied in length toprovidesome latitude between the final sealing of the exhaust conduit and theinstant at which the intake is opened. This feature, which I call thecontrolled degree of overlap, allows the original design of themechanism for a given result independent of adjustment of the camshafts.

During the exhaust stroke, as shown in Fig. 2, the sleeve is in itsupper position and the exhaust gases pass around the open poppet valveand out through the exhaust conduit I8. At the conclusion of the exhauststroke the sleeve 35 is lowered and seals off the exhaust. The sleeveproceeds on downwardly, as shown in Fig. 3, to open a port between itsupper portion and the annular boss 33. Thus intake gas may be suckedpast the sleeve and past the poppet valve'into the explosion chamber ofthe cylinder. At the termination of this operation the poppet valvecloses and the piston 42 rises to effect the compression stroke, whichis immediately followed by ignition and the power stroke in a mannerwell known in the art and not further described.

To actuate the sleeve 35 the mechanism shown in Fig. is provided. Thisconsists of a pair of upwardly extending ears 33 on opposite sides ofthe sleeve and extending above the spring cover 40, which surrounds thevalve casing 20. Each ear is provided with a horizontal lug 42 toposition the compression spring 45 between it and a shoulder on top ofthe cylinder head. The normal tendency of the springs 45 to retain thesleeve in the upper position shown in Fig. 1 is counteracted by cams 41on a camshaft 50 which is driven, as well understood, in timedsynchronism with the crankshaft. To actuate the poppet valve, a cam 52is provided, adapted to ride over a cap 53 bearing on top of the valvestem and guided in a guideway 54 of the valve cap 40. A spring ring 55is secured to the upper end of the valve stem and a compression spring5'! is interposed between the ring and the portion 3| of the core 30.

From the present mechanism just described, it will be apparent that thesleeve and poppet valve are normally retained in the upper positionsshown in Fig. 1, due to the action of their respective springs and thatthe downward motion of each valve member is effected by thecorresponding cams on the cam-shaft 50.

From the foregoing description it will be apparent that I have providedan improved valve mechanism by which a single valve opens into the powercylinder and when open serves as a passage for both intake and exhaustgases and improves the volumetric efficiency of the engine. Thecontinually cooling efiect of intermittent charges of intake gas largelynullifies the harmful effects of the hot exhaust gas and also preventsthe precipitation of carbon at the valve seat. The controlled degree ofoverlap in the sleeve 35 permits entirely sealing either the intake orexhaust conduit to the poppet valve before the other passage is opened.

Other modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the structureherein disclosed, provided the means The depth of the valve stated byany of the following claims or the equivalent of such stated means beemployed.

I therefore particularly point out and distinctly claim as my invention:

1. In an explosion engine, a cylinder structure, a piston in saidcylinder, a valve casing in communication with said cylinder andconcentric therewith,.a valve seat in said piston cylinder, acore insaid valve casing with a valve stem guide coincident with the valveaxis, a valve with a stem slideable in said guide to coact with saidseat and seal the cylinders and easing from each other, resilient meansto normally seat said valve, an intake and an exhaust conduit eachopening to said valve casing, a sleeve slidable in said valve casingbetween the core and side wall portion to control passage of gas betweenthe intake conduit and the valve casing and between said exhaust conduitand said valve casing, said sleeve acting to completely seal one conduitfrom said valve casing before openingthe other conduit to said valvecasing, and means to actuate said valve and said sleeve.

2. In a valve mechanism for an internal combustion engine, a cylinder, apoppet valveand a seat therefor in communication with said cylinder anda casing, a sleeve valve mounted to reciprocate coaxially with thepoppet valve in said casing, ,a core in said casing an exhaust conduitand an intake conduit in communication with said casing, one of saidconduits opening past said sleeve valve axially of said cylinder, andthe other opening transversely thereof in a region closely adjacent saidfirst opening, said sleeve valve coacting with said core to control saidaxial opening with the inner axial face thereof and to control saidtransverse opening with the outer axial face thereof, means toreciprocate said sleeve valve to alternately open said intake and saidexhaust to effect a passage of intake and exhaust gas past said poppetvalve and seat, said sleeve formed to seal said intakeconduit in aregion closely adjacent said exhaust conduit to prevent the accumulationof an appreciable volume of exhaust gas in said casing after saidexhaust conduit is closed.

3. In an explosion engine, a cylinder block having a cylinder, a valvecasing in communication therewith, said casing having two ports openingtherein, a stationary core in said casing, a sleeve valve in saidcasing, said sleeve valve being adapted for coaction with said core forsealing one of said portsand having a surface adapted to cover the otherof said ports.

4. In an overhead valve internal combustion engine, the combination of avalve casing having two ports and an aperture opening therein, a coreprojecting into said casing, a valve member slidable within the core forclosing said aperture, a sleeve having an outer axial surface adaptedfor covering one of said ports and an inner axial surface adapted forcoaction with said core for controlling the other of said ports.

5. In a valve mechanism, the combination of a valve casing having anopening for communication with a power cylinder, a conduit opening intosaid casing, a core projecting into said casing, a valve member slidablewithin the core for closing said opening, a sleeve in sliding engagementwith said casing and said core, means for intermittently breaking theengagement between said sleeve and said core whereby said conduit andsaid opening communicate through the opening of said sleeve.

6. In a valve mechanism, a valve casing having therein two openings, asleeve slidable in said casing between said openings; a poppet valvemember associated with the sleeve, means for sealing communicationbetween the valve member and the sleeve and means for actuating saidsleeve whereby said openings are intermittently in communication witheach other.

'7. In an explosion engine, a cylinder structure, a cylindrical valvecasing, a valve seat in communication with said cylinder and saidcasing,

10 a core in said casing having a valve stem guide therein, a valve Witha stem slideable in said guide for coaction with said valve seat forsealing said valve casing from said cylinder, an intake conduit and anexhaust conduit each opening in said valve casing, a sleeve valve forcovering one of said conduits, the other of said conduits beingcontrolled by coaction between said casing, sleeve valve and core, andmeans for actuating said valves.

HARRY L. I-IOSTERMAN.

